1. Field of the Invention
The present invention relates to a moving picture transmission apparatus, a moving picture transmission system, a moving picture transmission method, and a program.
2. Description of the Related Art
In recent years, it has become necessary to transmit data such as a moving picture through a transmission path such as the Internet with little delay. For example, when transmitting the moving picture in real time, it is necessary to transmit moving picture data with a delay equal to or less than a frame interval of the moving picture.
For this reason, Japanese Patent Application Laid-Open Publication No. 2007-311924 discloses a technique of dividing data corresponding to one picture into line blocks configured with a predetermined number of pixel lines and compressing the line blocks as block data (a line block unit scheme).
According to the technique, even when all data corresponding to one picture is not completely captured, a transmission side can start a subsequent process for each block data. Similarly, even when all data corresponding to one picture is not completely received, a reception side can start a subsequent process for each block data. Therefore, if a propagation delay of a transmission path is sufficiently small, the moving picture can be transmitted with a delay equal to or less than the frame interval.
However, depending on a display device that displays the moving picture, there is a case where all data corresponding to one picture is required for display. In this case, even when the subsequent process can start for each block data, the moving picture cannot be displayed until the subsequent process on all block data corresponding to one picture is completed. For this reason, a display point in time of the moving picture depends on a point in time when the subsequent process of block data finally captured among block data corresponding to one picture is completed.
However, in the typical moving picture transmission, block data is compression-encoded at a predetermined compression rate at a transmission side, is transmitted through a transmission path, and is compression-decoded at a reception side. In the moving picture transmission of the line block unit scheme, there are many cases where block data that is late in capture start order among block data corresponding to one picture has no time margin from a capture start point in time to a display point in time.
Further, for transmission of the moving picture, as an error correction technique at the time of transmission, a forward error correction (FEC) coding scheme is frequently used. In the FEC coding scheme, a transmission side performs redundant coding on original data and transmits a plurality of packets including a redundant packet through a transmission path. A reception side receives a predetermined number of packets among the plurality of packets and decodes the original data.